Re: RFR(XXS): 8242485: Null _file checking in fileStream::flush()

[Denghui Dong]

Hi,
Thank you for the review and point out other methods need to check _file.
In addition to "fileStream::flush", I found there are still four methods need to check _file in fileStream: read, readln, eof, rewind.
but those methods will crash if _file is NULL, and I didn't find any caller of them(Maybe I am wrong),
so I think it's more appropriate to add assert check to those methods.

Webrev: http://cr.openjdk.java.net/~ddong/8242485/webrev.01/

Could you review it again, and sponsor it if everything is okay?

Testing: teir1
==============================
Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR
   jtreg:test/hotspot/jtreg:tier1                     1516  1516     0     0
   jtreg:test/jdk:tier1                               1904  1904     0     0
>> jtreg:test/langtools:tier1                         4031  4029     2     0 <<
   jtreg:test/nashorn:tier1                              0     0     0     0
   jtreg:test/jaxp:tier1                                 0     0     0     0
==============================
There are two unrelated test failures in langtools: jdk/javadoc/tool/CheckResourceKeys.java  and tools/javac/processing/model/TestSymtabItems.java 



------------------------------------------------------------------
From:Yasumasa Suenaga <suenaga at oss.nttdata.com>
Send Time:2020年4月11日(星期六) 09:22
To:董登辉(卓昂) <denghui.ddh at alibaba-inc.com>; hotspot-dev <hotspot-dev at openjdk.java.net>; hotspot-runtime-dev at openjdk.java.net <hotspot-runtime-dev at openjdk.java.net>
Subject:Re: RFR(XXS): 8242485: Null _file checking in fileStream::flush()

Hi Denghui,

null check lacks in other place too.
Can you fix it?

   http://hg.openjdk.java.net/jdk/jdk/file/97d5d0cd1085/src/hotspot/share/utilities/ostream.cpp#l554


Thanks,

Yasumasa


On 2020/04/10 21:34, Denghui Dong wrote:
> Hi team,
> 
> Could you please review this small patch?
> 
> JBS: https://bugs.openjdk.java.net/browse/JDK-8242485
> webrev: http://cr.openjdk.java.net/~ddong/8242485/webrev.00/
> 
> I found the method "fileStream::flush()" lacks null check before fflush  which will cause
> all open output streams are flushed by fflush() if _file is NULL.
> 
> Thanks,
> Denghui Dong
>